Forming tools



R. E. GRANT Aug. 12, 1969 FORMING TOOLS v Filed Feb. 6, 1968 RAYMOND 21mm GRANT.

mvamv. mmmamwum United. States Patent US. Cl. 72-450 Claims ABSTRACT OF THE DISCLOSURE A machine for hot forming taper points on chisels, moils, and the like, having two jaws arranged for movement into a position in which the jaws define tapered faces for a tapered point, and a power source arranged to move one of the jaws towards such a position.

The invention relates to a machine for use in hot forming of taper points on cold chisels, moils and like tools. The invention may be applied to the production of new tools from bar or to the re-forming of used tools.

The invention provides a machine for the above purpose which comprises a pair of opposed substantially fiat jaws, at least one of which is mounted for pivotal movement, and power means to pivot the jaw(s) from an open position to a closed position at which the jaws are at an acute angle to one another (i.e. at the desired angle of taper of the chisel).

In the operation of the machine a heated rod blank or used tool to be reformed is placed between the jaws and the jaws are then closed deforming the blank or tool to the desired taper. When in the closed position the jaws may be in contact at the apex of the angle or may be separated a small distance appropriate to the thickness of the sharpened edge of the final tool.

Preferably the two jaws are pivotally mounted on a common frame.

In one form of the invention the movable jaw is pivotally supported on a frame to which the fixed paw is secured and the power means comprise a hydraulic jack acting between the said one jaw and the frame.

It is preferred that the jaws operate between a pair of opposed side members for supporting the sides of the tool.

More specifically the invention provides a machine for hot forming taper points on chisels, and the like, and comprising a frame, a first jaw attached to the frame, means to prevent movement of the first jaw away from a tool forming position in one direction, a second jaw pivotally attached to the frame, and means to urge the second jaw towards the first jaw in said one direction, the arrangement being such that when in the tool forming position the jaws define an acute angle corresponding to the desired taper of the chisel or the like.

Preferably the jaws are mounted for pivotal movement about the same axis.

A specific embodiment of a machine according to the invention will now be described, by way of example, with reference to the accompanying drawings in which:

FIGURE 1 shows a side view of the machine with the jaws in the closed position, and

FIGURE 2 shows a plan view of the machine.

10 and an upright pillar 11. The pillar is constructed of two channels 12 of which the lower ends are welded to the base.

Towards the top of the pillar there is secured therein a transverse pin 14 which acts as an anchor for one end of a fixed jaw member 15 and as a pivot pin for a pivoted jaw member 16.

3,460,371 Patented Aug. 12, 1969 The member 15 is a rectangular section bar through which passes a pin 18 which bears againt the channels 12 and may be held thereto by U bolts, not shown. The member 15 is accordingly supported against clockwise rotation, as seen in FIGURE 1. It is also held against anti-clockwise rotation but this is a matter of convenience and is not essential to the invention.

A double-acting hydraulic jack 20 is connected between the member 16 and the base of the pillar and is operable to rotate the member anti-clockwise from the jaws-closed position shown, to an open position, and then back to the closed position.

The member 16 is constructed of two side plates 16a and 16b which are secured in spaced relation by an L- shaped member 21 welded between the plates. The member 15 fits between the side plates.

Welded to the member 15 and to the member 21 respectively there are two replaceable jaw plates 22, 23.

Supported on the base there is a hydraulic pump 25 with an electric driving motor 26 and flexible coupling. The pump supplies high pressure operating fluid to the jack 20 via a non-return valve 27, a two-way manually operable control valve (not shown) supported on the pillar and appropriate flexible pipes. A reservoir for hydraulic fluid is provided within the base.

In the operation of the machine, the jack is operated to open the jaws by anti-clockwise rotation of the member 16. A heated blank or tool (shown in chain dotted lines) is inserted between the jaws and between the side plates 16a, 16b. The jaws are then closed to the position shown in FIGURE 1 thereby shaping the tool to the angle shown between the jaw plates and to the space between the side plates.

The invention is not limited to the constructional details of the above example. For instance the jack may be pneumatically operated insttead of hydraulically.

The machine described above with reference to the accompanying drawings may be used by inexperienced operators to sharpen bits of pneumatic tools. If pneumatic tools are used with blunt bits time and effort is Wasted. Consequently, it is advantageous if a tool operator can quickly and simply sharpen a tool bit in situ, and obtain consistently shaped working faces.

I claim:

1. A machine for hot forming taper points on tools and comprising a frame, a first jaw connected to the frame, a second jaw pivotally attached to the frame and pivotally movable from an open position in which it is spaced away from the first jaw towards the first jaw to a tool forming position in which it defines with the first jaw an acute angle corresponding to the undesired taper of the tool, drive means operative to urge the second jaw from the open position to the tool forming position and stop means preventing movement of the first jaw from the tool forming position at least in the direction away from the second jaw.

2. A machine as claimed in claim 1 in which the drive means to urge the second jaw towards the first jaw comprises a hydraulic jack acting between the said second jaw and the frame.

3. A machine as claimed in claim 1 having a pair of opposed side members for supporting the sides of the tool.

4. A machine as claimed in claim 3 in which the opposed side members form part of one of the jaws.

5. A machine as claimed in claim 4 in which the opposed side members are formed on the second jaw.

6. A machine as claimed in claim 1 in which the frame has two opposed upright portions, there is a pin extending between the opposed upright portions, and the jaws are mounted for relative pivotal movement about the axis of that pin.

of the frame when this first jaw is in the tool forming position.

8. A machine as claimed in claim 6 in which the means to urge the second jaw towards the tool forming position is a hydraulic jack connected to the second jaw at a point away from the pin, and to at least one of the two opposed upright portions aforesaid at a point away from the pin.

9. A machine as claimed in claim 2 in combination with a hydraulic pump, an electric driving motor for the pump, and means to connect the pump to the jacks.

10. A machine as claimed in claim 1 and having:

(a) a frame comprising a base and two opposed upright portions upstanding from the base and formed as spaced apart back to back channels;

(b) a pin extending between the upright portions at a position above the base;

(c) a first jaw comprising a bar of rectangular section mounted on the pin between the upright portions;

(d) a second jaw comprising two opposed side members pivotally mounted on said pin on either side of 4 the first jaw and between the upright portions, and a member extending between the side members away from the pin;

(e) replaceable jaw plates for attachment to the jaws aforesaid; l

(f) abutments extending from the bar of rectangular section and arranged to bear on the upright members;

(g) a hydraulic pump mounted on the base;

(h) a hydraulic jack pivotally'connected to the base and to a pin joining the two opposed side members at a point away from the pin;

(i) means to connect the point to the jack; and

(j) an electric motor arranged to drive the pump.

References Cited UNITED STATES PATENTS 1,040,282 10/1912 Crary 7245O CHARLES W. LANHAM, Primary Examiner GENE P. CROSBY, Assistant Examiner US. Cl. X.R. 72453 @3 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION D d August 12, 1969 Patent No. 3 ,460 ,371

Inventor) Raymond Edwin Grant It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

[- Column 2, line 51, change "undesired" to desired.

SIGNED AND SEALED FEB 24 1970 J' Amt:

EdwardlLFletdaex-Jr. mm 1- mm, JR.

Oomissioner of Patents Atteating Officer 

